Many are repeats or "loyal" buyers. In massachusetts brothel bust they went after the most repeating ones out of more than 2800 numbers they found. Out of these almost 3000 ones they identified 34 individuals. These 34 individuals had interaction in 100s of messages. Now I don't know if that mean 100s of visits or multiple messages accounted for each visit. The clientele was described as "wealthy and well-connected" including doctors, lawyers, corporate executives, military officers, scientists, professors and a Cambridge city councilor.
Someone was saying since client list contain influential people, they won't go after clients but Massachusetts trial speaks otherwise. They specifically went after clients regardless of their influence.